Process of making zinc oxide



y 17. J. F, cREGAN PROCESS 0F MAKING ZINC OXIDE Filed Oct. 25. 1924 x, u* Etang ATTORNEY Patented May 17, 1927.

1,628,953 PATENT orifice. N

JOHN F. CREGAN, F PUEBLO, COLORADO, ASSIGNOR TO AMERICAN SMELTING .AND

BEFINING COMPANY, 0F NEW YORK, N. Y., .A.CORPORATION OF NEW JERSEY.

` :PROCESS or MAKING zinc oxrnn.

Application led October 25, 1924. Serial-No. 745,794.

My present invention relates to a method of treating zinc fumes for the production of zinc oxide and to apparatus by meansl ofrwhich such process ispracticed and especially to a method and apparatus for producing zinc oxide from such va\por ized zinc in one continuous but simple and economical operation. A

The invention relates articularly to a method and process wherelgy zinc is distilled from zinc bearing material and impurities are removed from the zinc fumes and a certain vdegree of oxidation attained after which air is mixed with the fumes so as to form a thorough and intimate mixture with consequent further oxidation of the zincI fumes by the oxygen of the air admixed therewit The invention further consists in the new and novel features of operation and the new and original arrangements and combinations of steps in the process hereinafter described and more particularly set forthin the claims. f

AccordingI to` my invention, zinc vapor from a suitable source such as a reverberatory furnace, is vaporized and passed through a settling chamber in which im- .purities will be settled out. From the Settling chamber the fumes pass through main lues in close proximit to an oxidizing chamber. Short connectlng lues having air inlets connect the said mam ilues with said oxidizing chamber. Through the coming together of the .zinc fumes and the air at a plurality of points and then passing therefrom innn'ediately into the oxidizing chamber there is secured a rapid, eticient and complete mixture of the zinc fumes and the. air, resulting in complete and uniform oxidation of the fume.

The oxide Vmay be collected b'y suitable means such as are well known in the art.

In the drawings: Fig. 1 is Va plan view in section taken alon line 1 1 of Fig. 2 looking in the direction vof the arrows, and shows a reverberatory furnace, a settling chamber, {lues leading from the upper part of said chamber, and an oxidizing chamber positioned below said fines and communicating therewith through mixing ues having air 'inlet open- I ings. y

v ig. 2 1s an elevation view in section of the apparatus of Fig- 1 taken`along line 2 2 of Fig. 1 and Fig. 3 is a 'sectional elevation view taken along line 3 3 of Fig. 1 and looking in the v direction of the arrows.

In an embodiment of my invention illus` trated in the accompanying drawings there is diagrammatically shown' a' reverberatory furnace 1, suitable for smelting zinc carrying material and vaporizing the zinc, although any form of apparatus for producing zinc vapor may baemployed. .Through a short flue 2, the reverberatory furnace opens into a settlin chamber 3 which is suiciently large to relieve the furnace of any back pressure from the fumes and preferably s approximately twice the volume of the furnace. From the upper part of the settling l chamber extend two large or main ilues 4-4 which may be separated from each other by a unitary wall. 5.y Y

Adjacent to and preferably having its walls continuations of the walls of the settling chamber is a. burning and oxidizing chamber 6. The roof 7 of said refining chamber 6 is spaceda comparatively short distance from the floor of the mam flues 4 4; connecting the ues 4 4 with the chamber 6 are a plurality ofi relatively small passages dr mixing lues 8 8 which extend between the wall of main fines 4 4 and the roof 7. The openings 9 9 in mixing vlues 8 8 admit-air into the flue -for the purpose of mixing it thoroughly and intimately with the vzinc fumes passing from ,flues 4 4 to chamber 6. The' amount of air admitted through openin 9 is regulated by means of the hinged c osures 10 10 whose position may be adjusted by means of the chains 11 11 which connect to said doors 10 10. Said chamber 6 exhausts into the flue l12 passing outwardly from the wall 13. Y

In the use and operation of my invention a charge of.zinc ore or other zinc bearing material is fed to the` furnace 1 and the zinc vaporized. The vzinc fumes pass from the furnace 1 through the Hue 2 into the settling chamber 3 where foreign and solid material will settleout as a result of a decrease in rate oftravel through said chamber which is of greater volume than said furnace. In the furnace 1 and in the chamber 3 the zinc will be oxidized to some extent (unless ofl made by those course the zine vaporized in a reducing atmosphere). The zinc fumes, now containing Zine'oxide as well as metallic Vapor, pass from the settling chamber freed of foreign material through iues 4 4, flues 8 8 and into the chamber 6. As the fumes pass through iues 8 8 they are admixed with the air admitted through ports 9 9 and complete oxidation is e'ected in the chamberl The settling chamber is maintained at a relatively high temperature but below the temperature of the furnace for example approximately at or about 200001K, control of the temperature being secured by making the Walls and roof of the settling chamber of proper materials and thicknesses, by varying the heat insulation thereon, and also by controlling the temperature of the gases entering said chamberl 3.

The air readily reacts with the fumes so that a vigorous combustion of the fumes takes place in the oxidizing chamber. This intimate mixture of the fumes and air as obtained by the use of a plurality of mixing flues results in 'a rapid and economical production of a high grad-e zinc oxide.

Although I have shown and described and have pointed out in the annexed claims, certain novel features of my invention, it will be understood that various omissions, substitutions and changes inthe several steps of my process and in its operation may be skilled in the art Without departing from the spirit of the invention.

Having thus described my invention, I claim:

l. The process of producing zinc oxide directly from zinc bearing material, which 2comprises smelting the material, passing the distilled zinc vapor to a settling chamber to settle out foreign material, removing said vapor and mixing air therewith, then conducting said mixture into a burning chamber and permitting combustion therein to convert the zinc vapor into oxide.

2. The process of producing zinc oxide directly from zinc bearing material, Which comprises smelting the material, passing the distilled zinc vapor to a settling chamber maintained at a relatively high temperature to settle out foreign matter, removing the zinc vapor through mixing flues, admitting air into said flues and causing an intimate mixtureof the air and the vapor, then conductin said mixture into a burning chamber maintained at a temperature to support rapid oxidation( to convert the zine vapor into oxide. Y

3. The process of producing zine oxide directly from zinc bearing material, which comprises smelting the material, passing the distilled zine vapor into a settling chamber, continuously removing the zine vapor through mixing flues, admitting air into said fiues in volume sufficient to convert all of the vapor into oxide, and then conducting said mixture into a burning chamber.

4L. The process of producing zinc oxide comprising smelting Zinc bearing material to distill zinc therefrom as a fume or vapor, passing said -vapor in a plurality of relatively small vstreams into a separate chamber, commingling air with said streams in volume sufficient to oxidize all of the zinc, mixing the air intimately with the vapor before entering said chamber and causing oxidation of the zine vapor in said chamber, and then collecting the zinc oxide.

5; The process of producing zinc oxide directly from zinc bearing material comprising smelting said material to distill zinc therefrom as a fume or vapor, dividing said vapor into a plurality of relatively small streams and passing the same into a separate chamber, commingling air With said streams in volume suflicient to oxidize allof the zinc before entering said chamber, causing oxidation of the zinc vapor in said chamber, and then collecting the zine oxide.

' 6. The process of producing zinc oxide directly from zinc bearing material comprising smelting said material to distill zinc therefrom as a fume or vapor, dividing said vapor into a plurality of streams, subdividing said streams into a plurality of smaller streams and passing the same into a separate chamber, commingling air With said smaller streams in volume sufficient to oxidize all of the zinc before entering said chamber, causing oxidation of the zine vapor in said chamber, and then collecting the zinc oxide.

7. The process of making zinc oxide, comprising dividing a body of zine vapor into a plurality of smallstreams, commingling air with said streams in volume sufficient to oxidize all of the zinc vapor', passing said mixture into a common burning chamber to oxidize the zinc, and thentcolleeting the zinc oxide.

8. The process of making zinc oxide, which comprises dividing a body of zinc vapor at a relatively high temperature into a plurality of relatively small streams, commingling air With said streams in volume sufficient to oxidize all of the zinc vapor and passing said mixture into a burning chamber to oxidize the zine.

9. The process of making zinc oxide, which comprises dividing a body of zine vapor at a relatively high temperature into a plurality of relatively small streams, mixing air With said streams While the vapor is flowing through a restricted space in volume sulicient to oxidize all of the zinc vapor and passing said mixture into a burning chamber to oxidize the zinc.

10. The process of makingv zinc oxide,

which consists in passing zinc vapor in relatively small quantities through a restricted the vapor is flowing therethrough and causing the air to mix intimately with the vapor and then conducting said 4mixture into a chamber at a temperature suiiicient to support violent combustion.

11. The`- process of making zinc oxide, which consists in passing zinc .vapor inrelatively small uantities tbhrough a restricted passage, admitting air to said passage While the vapor is flowing therethrough and causing the air to mix intimately withthe vapor, conducting said mixture into a separate chamber to oxidize the zinc therein and then collecting the oxide.

12. The process of making oxide, -which consists in passing zinc vapor in a continuous stream through ilues havmg a limited cross sectional area to promote rapid flow of the gas therethrough, causing the air' to commingle with the vapor in said flue, and burning the mixture in a chamber communicating with said Hue. i

13. The process of making zinc oxide, which consists in passing zinc vapor in relatively small quantities through a plurality of mixin flues, admitting vair to each of said iues whi e the vapor is owing therethrough, causing an intimate mixture of the vapor and air in said lues, and supplying said mixture from said iiues t0 a burning chamber at atemperature suiicient to support violent combustion.

14. The process of making zinc oxide, which consists in passing zinc vapor in relatively small quantities through a plurality of mixing flues, admitting a regulated quantityof a'ir to each of said iues while the vapor is flowing therethrough involume sufficient to oxidlze zinc, causing an intimate mixture of the vapor and air in said ues, and supplyingsaid mixture from said ilues to a common burning chamber at a temperature suliicient to support violent combustion.

-15. The, rocess of treating zinc bearing ore to pro uce zinc oxide in a continuous operation directly ,therefrom which comrises smelting the ore in a. reverberatory urnace under normal smelting conditions, pgssing the zinc vapor to a. settling chamr maintained at a high temperature bel-ow y the temperature of the furnace and having a volume greater than the furnace to settle out foreign matter mingled with said vapor and continuously removing portions of the zinc vapor from said settling chamber, passing the same through mixing liues, mixing air withA the vapor in said l'lues, in volume suicientto support intense combustion, admitting said mixture of vapor and air into a separate burning chamber, and permitting combustion therein.

16,. The process of treating zinc bearing material to produce zinc oxide directly therefrom which comprises smelting the ore in a reverberatorl furnace, passing the zinc vaporto a setthno` chamber having a volume greater than the furnace to settle-out foreign matter. mingled with said vapor and continuously removing portions of the zinc vapor from said settling chamber, passing the same through mixing flues, mixing air with the vapor in said liues in volume suliicient to oxidize the zinc vapor, admitting said mixtureof vapor and air in a sepa-rate burning chamber, and permitting combustion therein.

17. The process of treating zinc bearing material to produce zinc oxide directly therefrom in a continuous operation, which comprises smelting the ore in a reverberatory furnace under normal smeltinr conditions,

passing the zinc vapor to a sett ing chamber i having a temperature above the distilling point of the zinc and below the temperature of the vfurnace and having a volume greater than the furnace to settle out foreign matter mingled with said vapor, c'ontinuously removing zinc vapor from the settling-chamber in a plurality of streams subdividing said streams and mixing air therewith in a volume -at least sufficient to oxidize the zinc vapor, admitting said mixture of vapor and air into a separate burning-chamb er to oxidize the zinc vapor and collecting the zinc oxide.

` 18. The process ofv treating' zinc bearing material to produce zinc oxide directly therefrom in a continuous operation, which comprises smelting the ore in a reverberatory furnace under normal smelting conditions,

assing the `zinc vapor and products of comustion to a settling chamber having a volume greater than the furnace to settle out foreign matter, continuously removing zinc vapor and products of combustion from the settling chamber, subdividing said vapor and passing the same through mixing ilues, in-

troducing air into said mixing ues in volume suflicient to oxidize the zinc vapor, ad-

mitting said mixture into a separate burning chamber to burn the zinc vapor and collect- .ioHN F. CREGAN. 

